Page 66 - AJWEP-22-6

Asian Journal of Water, Environment and Pollution. Vol. 22, No. 6 (2025), pp. 60-72.
doi: 10.36922/AJWEP025240195

ORIGINAL RESEARCH ARTICLE

Optimization of pine sawdust densified biofuel: Effects
of process parameters on fuel quality and temperature

distribution

Zhuoying Chen , Zhiyuan Ma , Zhongjia Chen , Zhongsai Li ,
and Xiangyue Yuan*
Biomass Laboratory, School of Technology, Beijing Forestry University, Beijing, China
*Corresponding author: Xiangyue Yuan (yuanxiangyue@bjfu.edu.cn)

Received: June 13, 2025; 1st revised: July 10, 2025; 2nd revised: July 18, 2025;
Accepted: July 21, 2025; Published online: August 7, 2025

Abstract: The valorization of forestry waste into densified biofuels is critical for sustainable energy development.
This study investigates the optimization of the densification process for pine sawdust by examining the effects of
key parameters on the final product quality, specifically focusing on the uniformity of the internal temperature
field. A four-factor, mixed-level orthogonal experiment was designed, investigating forming pressure, moisture
content, binder addition ratio, and heating temperature. The temperature mean square deviation (MSD) was utilized
as the primary response variable to quantify thermal distribution uniformity. Analysis of variance (ANOVA) was
performed to determine the statistical significance of each factor, and a multivariate regression model was established.
Results from ANOVA indicated that the descending order of significance for factors impacting temperature MSD
was: moisture content > forming pressure > heating temperature > binder addition ratio. A statistically significant
interaction effect was identified between forming pressure and heating temperature. Response surface methodology
was employed to optimize these two significant factors. The optimal conditions for minimizing temperature MSD,
while maintaining constant moisture content and binder ratio, were determined to be a forming pressure of 10 MPa
and a heating temperature of 190°C. By optimizing process parameters to achieve a more uniform temperature
field, the quality and stability of the resulting pine sawdust densified fuel were significantly improved. This work
provides a quantitative theoretical basis and key technical parameters for the scale-up and industrial application
of biomass fuels in boilers and residential heating systems, thereby promoting the development of a low-carbon
circular economy.

Keywords: Densified fuel quality; Binders; Fuel quality; Temperature distribution; Mechanical Properties;
Forestry waste

1. Introduction development. In China, potential biomass resources
from agricultural and forestry waste amount to 850
In the face of global resource scarcity, environmental million and 340 million tons, respectively, with energy
pollution, and intensifying climate change, efficient crops contributing an additional 740–960 million tons.
1
management and resource utilization of forestry Depending on development levels, biomass energy
waste have become critical for achieving sustainable potential is estimated at approximately 1.9–41.2 EJ,

Volume 22 Issue 6 (2025) 60 doi: 10.36922/AJWEP025240195